Electric foldable bed capable of adjusting to a predetermined position by detecting the number of rotations of a motor

ABSTRACT

An electric foldable bed capable of being adjusted to a memorized position has a fold bed having motors connected to a headboard and a footboard. A microcomputer is installed on the bed frame and used for controlling the motors. The microcomputer has a computing section, a memory section, a register section and a comparing section. The computing section detects a position of each motor and computes elevation angle data provided by the memory section, the register section and the comparing section. The memory section is used to store predetermined elevation angle data, the register section is used to receive control commands and store the elevation angle data input by the computing section. The comparing section is used for comparing the elevation angle data from both the memory section and the register section. The sensor is installed onto each motor and used for sensing a rotational number count of the motor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electric foldable bed, and more particularly to an electric foldable bed that is capable of detecting the number of rotations of a motor using a microcomputer to accurately control the elevation angle of the folded bed and store preferred elevation angles for users.

2. Description of the Related Art

Typical electric folding beds usually have elevation motors on their bed frames. An output end of the elevation motor is connected to a bed board, such that when the elevation motor is turned on the bed board is pushed to lift or lower an elevation angle of the bed board. Therefore, users can sit upright on the electric folding bed or have their legs lifted. However, with clockwise and counter-clockwise rotations of the elevation motor, the bed board is lifted or lowered, but the electric folding bed does not have any predetermined elevation angle and is not able to store elevation angle values for the user, and so it is difficult to repeat a previous elevation angle.

Therefore, it is desirable to provide an electric foldable bed to mitigate and/or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide an electric foldable bed that is capable of detecting the number of rotations of a motor using a microcomputer to accurately control the elevation angle of the folded bed and store preferred elevation angles for users.

In order to achieve the above-mentioned objectives, an electric foldable bed comprises: a folding bed, a microcomputer, sensors and a controller. The folding bed has a bed frame pivoted with a headboard and a footboard at opposite ends, and two motors attached to an underside of the bed frame. The motors are connected to the headboard and the footboard and generate respective elevation angle changes. Each motor further comprises a limit switch, wherein when the headboard or the footboard is lowered to effectively no elevation angle, the respective limit switch is activated to stop the motor and sets this position as a start position for the respective elevation angle data. The folding bed further includes an extension board pivoted to a free end of the footboard, which is capable of forming a triangle with two elevation angles with the footboard. The microcomputer is disposed on the bed frame and is used for controlling the motors, and the microcomputer further comprises a computing section, a memory section, a register section and a comparing section. The computing section detects a position of the motors and computes elevation angle data provided by the memory section, the register section and the comparing section. The memory section is used to store predetermined elevation angle data, the register section is used to receive control commands and temporarily store the elevation angle data input by the computing section. The comparing section is used for comparing the elevation angle data from both the memory section and the register section. The sensor is installed onto each motor and used for sensing a rotating number count of the motor and transmitting a serial pulse wave signal to the computing section of the microcomputer. The controller is used for inputting the control command and transmitting signals to the register section of the microcomputer.

Compared to the prior art, the electric folding bed of the present invention utilizes sensors to detect the number of rotations of the motors and the microcomputer compares the current elevation angle and the predetermined elevation angle to determined a required number of rotations to control the elevation angles for the folding bed. Furthermore, the user can set up preferred elevation angles.

Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a functional block drawing of an embodiment of the present invention.

FIG. 3 is a schematic drawing showing a headboard being lifted and a footboard that has no the elevation angle according to an embodiment of the present invention.

FIG. 4 is a schematic drawing showing movement of a motor according to an embodiment of the present invention.

FIG. 5 is a movement schematic drawing showing the increase of an elevation angle according to an embodiment of the present invention.

FIG. 6 is a graph of elevation angle and rotation number according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer to FIG. 1 and FIG. 2. An electric foldable bed comprises: a folding bed 10, a microcomputer 20, sensors 30 and a controller 40. The folding bed 10 has a bed frame 11 pivoted to a headboard 12 and a footboard 13 at opposite ends, and two motors attached to an underside of the bed frame 11. The motors 14 are connected to the headboard 12 and the footboard 13 and generate respective elevation angle changes. Each motor 14 further comprises a limit switch 15, wherein when the headboard 12 or the footboard 13 is lowered to effectively no elevation angle, the respective limit switch 15 is activated to stop the motor 14 and sets this position as a start position for the respective elevation angle data. The folding bed 10 further includes an extension board 16 pivoted to a free end of the footboard 13, which is capable of forming a triangle with two elevation angles with the footboard 13. The microcomputer 20 is disposed on the bed frame 10 and is used for controlling the motors 14, and the microcomputer further comprises a computing section 21, a memory section 22, a register section 23 and a comparing section 24. The computing section 21 detects a position of the motors 14 and computes elevation angle data provided by the memory section 22, the register section 23 and the comparing section 24. The memory section 22 is used to store predetermined elevation angle data, and the register section 23 is used to receive control commands and temporarily store the elevation angle data input by the computing section 21. The comparing section 24 is used for comparing the elevation angle data from both the memory section 22 and the register section 23. The sensor is installed onto each motor 14 and used for sensing a rotating number count of the motor 14 and transmitting a serial pulse wave signal to the computing section 22 of the microcomputer 20. The controller 40 is used for inputting the control command and transmitting signals to the register section 23 of the microcomputer 20.

The headboard 12 and the footboard 13 are capable of the same movement type of movements; therefore, the following discusses only movement of the footboard 13. Please refer to FIGS. 2, 3, 4. First, a start position for the elevation angle data is set up; when the motor 14 drives the footboard 13 to a horizontal position, the motor 14 retracts and activates the limit switch 15; the limit switch 15 stops the motor 14, and the sensor 30 outputs a signal to the computing section 21 of the microcomputer 20. Meanwhile, the microcomputer 20 determines and orders the computing section 21 to force a start from 0, which defines the footboard 13 as being at the start position. When the user wants to increase the elevation angle of the footboard 13, as shown in FIGS. 5 and 6, the user inputs a command into the controller 40 which requests the microcomputer 20 to cause the motor 14 to operate according to the predetermined elevation angle data stored in the memory section 22. The computing section 21 calculates a distance between the position of the footboard 13 and the elevation angle data in order to control the motor 14 to rotate to lift up the footboard 13 by using an accumulating method, and during rotations of the motor 14, the sensor 30 detects the number of rotations of the motor 14, and then the sensor 30 sends out serial pulse wave signals to the computing section 21 of the microcomputer 20 to cause the motor 14 to rotate for a pre-stored number to push and lift the footboard 13 to a predetermined elevation angle required by the controller 40. On the other hand, when the user wants to reduce the elevation angle of the footboard 13, the microcomputer 20 determines a current elevation angle based on the previous number of rotations of the motor 14 and calculates a number of counter-clockwise rotations of the motor 14 by using a decrementing method, to control the motor to rotate counter-clockwise to lower the footboard 13 to reduce the predetermined elevation angle.

For further operations please refer to FIG. 5, FIG. 6 and FIG. 2. The user can select and store more than one elevation angle for the preferred positions. The controller 40 first sends a command for setting a preferred elevation angle to the microcomputer 20, and then the computing section 21 inputs the setting into the register section 23 for storage into the elevation angle data. When the user wants to adjust the footboard 13 to a preferred elevation angle, the comparing section 24 compares both the elevation angle data from the memory section 22 and the register section 23, to obtain a relative distance between the predetermined elevation angle data and the preferred elevation angle data and inputs it into the computing section 21 to calculate the number of rotations of the motor 14. Therefore, the microcomputer 20 controls the motor 14 to push and lift the footboard 13 to the preferred elevation angle stored by the user. With the above-mentioned movement, the various elevation angles of the folding bed 10 can be accurately controlled, and the user can set up his or her preferred elevation angles.

Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

1. An electric foldable bed capable of adjusting to a predetermined position by detecting the number of rotations of a motor, comprising: a folding bed having a bed frame pivoted with a headboard and a footboard at opposite ends, and at least two motors attached to an underside of the bed frame, the motors being connected to the headboard and the footboard and generating respective elevation angle changes; a microcomputer disposed on the bed frame and used for controlling the motors, the microcomputer comprising a computing section, a memory section, a register section and a comparing section, the computing section detecting a position of the motors and computing elevation angle data provided by the memory section, the register section and the comparing section, the memory section being used to predetermined elevation angle data, the register section receiving control commands and storing the elevation angle data input by the computing section, the comparing section used for comparing the elevation angle data from both the memory section and the register section; a sensor installed onto each motor and used for sensing a rotating number count of the motor and transmitting a serial pulse wave signal to the computing section of the microcomputer; and a controller used for inputting the control command and transmitting signals to the register section of the microcomputer.
 2. The electric foldable bed as claimed in claim 1, wherein the folding bed further includes an extension board pivoted to a free end of the footboard, which is capable of forming a triangle with two elevation angles with the footboard.
 3. The electric foldable bed as claimed in claim 1, wherein each motor further comprises a limit switch, wherein when the headboard or the footboard is lowered to effectively no elevation angle, the respective limit switch is activated to stop the motor and sets this position as a start position for the respective elevation angle data.
 4. An electric foldable bed capable of adjusting to a predetermined position by detecting the number of rotations of a motor, comprising: a folding bed having a bed frame pivoted with a headboard and a footboard at opposite ends, and at least two motors attached to an underside of the bed frame, the motors being connected to the headboard and the footboard and generating respective elevation angle changes; a microcomputer disposed on the bed frame and used for controlling the motors, the microcomputer comprising computing means, memory means, a register section and comparing means, the computing means detecting a position of the motors and computing elevation angle data provided by the memory means, the register section and the comparing means, the memory means being used to predetermined elevation angle data, the register section receiving control commands and storing the elevation angle data input by the computing means, the comparing means comparing the elevation angle data from both the memory means and the register section; a sensor installed onto each motor and used for sensing a rotating number count of the motor and transmitting a serial pulse wave signal to the computing means of the microcomputer; and a controller used for inputting the control command and transmitting signals to the register section of the microcomputer.
 5. The electric foldable bed as claimed in claim 1, wherein the folding bed further includes an extension board pivoted to a free end of the footboard, which is capable of forming a triangle with two elevation angles with the footboard.
 6. The electric foldable bed as claimed in claim 1, wherein each motor further comprises a limit switch, wherein when the headboard or the footboard is lowered to effectively no elevation angle, the respective limit switch is activated to stop the motor and sets this position as a start position for the respective elevation angle data.
 7. A method of adjusting a predetermined position of electric foldable bed, comprising steps of: a) preparing an electric foldable bed having a folding bed, a microcomputer, sensors, and a controller, the folding bed having a bed frame, a headboard, a footboard, and two motors attached to an underside of the bed frame, the motors being connected to the headboard and the footboard for generating respective elevation angle changes, each of the motors having a plurality of limit switches corresponding to the headboard and the footboard, the microcomputer having a computing section, a memory section, a register section, and a comparing section, the memory section being adapted for storing predetermined elevation angle data, the sensors being adapted for sending a rotating number count of the motor and transmitting a serial pulse wave signal to the microcomputer; b) lowering the headboard or the footboard to effectively no elevation angle to activate the respective limit switch to stop the motor and set this position as a start position for, the respective elevation angle data; c) inputting preferred elevation angle data of the user's preferred position into the microcomputer via the controller; next, the microcomputer inputs it into the register section for storage, the comparing section compares both the elevation angle data from the memory section and the register section to obtain a relative distance between the predetermined elevation angle data and the preferred elevation angle data, and finally the microcomputer inputs it into the computing section to calculate the number of rotations of the motor; and d) controlling the respective motors to lift up the headboard or the footboard according to the number of rotations of the motor for reaching the user's customized elevation angle. 